Dolphin House reef

Sha'ab El Erg is a horseshoe-shaped reef about an hour north of Hurghada with a sheltered sandy lagoon in its centre. A pod of spinner dolphins uses that lagoon as a daytime resting place, which is why the site is known as Dolphin House.

What to expect, honestly

These are wild animals and nothing is guaranteed. Sightings are common but not certain, and a responsible boat will tell you that before you leave rather than after. When the dolphins are present the encounter is on their terms — you enter the water quietly at a distance and they choose whether to approach.

• Two or three snorkelling stops on the reef itself, which is excellent regardless
• Hard coral gardens in shallow water, with rays and turtles seen fairly often
• Lunch aboard, back mid-to-late afternoon

How to behave in the water

Do not chase, do not swim into the middle of the pod, and never touch. Spinner dolphins sleep by day — they hunt at night in deep water — so the lagoon is where they rest. Boats that crowd them push them out of it, and pods have abandoned resting sites elsewhere in the world for exactly that reason. Operators who cut engines and keep their distance are giving you the better encounter as well as the sustainable one.

Spinner dolphins take their name from what they do: they leap clear of the water and rotate on their long axis, sometimes several full turns in a single jump. Nobody is certain why. The leading explanations are dislodging parasites and remoras, and signalling — the splash carries a long way underwater.

They live in fluid groups that merge and split through the day, and they are among the most social of the small cetaceans. In the Red Sea the pods are resident rather than migratory, which is what makes a site like this reliable enough to have a name.

Nocturnal hunters

Their day is the inverse of ours. At night they move offshore into deep water and feed on the deep scattering layer — the vast mass of small fish and squid that rises towards the surface after dark and sinks again at dawn. It is one of the largest daily migrations of biomass on the planet, and these dolphins follow it up and down.

By morning, full and tired, they return to shallow sandy lagoons where the bottom is bright, visibility is good and sharks are easy to spot. Resting there is a safety behaviour, and it is why disturbance at this particular site matters more than it would in open water.

A protected reef

Sha'ab El Erg lies within the Red Sea's protected-area network, with mooring buoys instead of anchoring and rules on how boats may approach the lagoon. Enforcement has improved considerably, and the resident pod has stayed — which, on a coast this heavily visited, is not a small thing.